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[PMID]: | 24095792 |
[Au] Autor: | Carvalho FA; Carvalho JW; Biazin E; Santiago PS; Tabak M |
[Ad] Endereço: | Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, SP, Brazil. |
[Ti] Título: | Characterization of Rhinodrilus alatus hemoglobin (HbRa) and its subunits: evidence for strong interaction with cationic surfactants DTAB and CTAC. |
[So] Source: | Comp Biochem Physiol B Biochem Mol Biol;167:23-9, 2014 Jan. | [Is] ISSN: | 1879-1107 |
[Cp] País de publicação: | England |
[La] Idioma: | eng |
[Ab] Resumo: | Rhinodrilus alatus is an annelid and its giant extracellular hemoglobin (HbRa) has a molecular mass (MM) of 3500kDa. In the current study, the characterization of MM values of the HbRa subunits, and the effects of surfactants and alkaline pH upon HbRa stability were monitored. Electrophoresis, MALDI-TOF-MS and AUC show that the MM values of HbRa subunits are very close, but not identical to the Glossoscolex paulistus hemoglobin (HbGp). The monomer d is found to exist in, at least, two isoforms: the main one, d1, displays a MM of 16,166±16Da, and the second one, d2, is less intense with MM of 16,490±20Da. For the trimer abc and tetramer abcd, single contributions around 51,470Da and 67,690Da were observed, respectively. Finally, the monomers a, b, and c, present MM values of 17,133, 17,290 and 15,506Da, respectively. Both CTAC and DTAB interact strongly with HbRa, and up to seven surfactant molecules are bound to the protein. On the other hand, spectroscopic studies show that HbRa is more stable at alkaline pH, as compared to HbGp. Thus, our data suggest that alkaline medium, up to pH10.0, induces the oligomeric dissociation, without promoting the subunits unfolding and heme iron oxidation. Our results suggest that the MM of the annelid hemoglobin subunits is conserved to a great extent in the evolution process of these species. |
[Mh] Termos MeSH primário: |
Compostos de Bis-Trimetilamônio/metabolismo Hemoglobinas/metabolismo Oligoquetos Subunidades Proteicas/metabolismo Compostos de Amônio Quaternário/metabolismo Tensoativos/metabolismo
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[Mh] Termos MeSH secundário: |
Animais Hemoglobinas/química Concentração de Íons de Hidrogênio Oxiemoglobinas/química Oxiemoglobinas/metabolismo Ligação Proteica Estabilidade Proteica Estrutura Quaternária de Proteína Subunidades Proteicas/química
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[Pt] Tipo de publicação: | JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T |
[Nm] Nome de substância:
| 0 (Bis-Trimethylammonium Compounds); 0 (Hemoglobins); 0 (Oxyhemoglobins); 0 (Protein Subunits); 0 (Quaternary Ammonium Compounds); 0 (Surface-Active Agents); 0 (cethyltrimethylammonium chloride); 15053-09-5 (decyltrimethylammonium) |
[Em] Mês de entrada: | 1409 |
[Cu] Atualização por classe: | 131202 |
[Lr] Data última revisão:
| 131202 |
[Sb] Subgrupo de revista: | IM |
[Da] Data de entrada para processamento: | 131008 |
[St] Status: | MEDLINE |
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